Heat wrap on winter lagers - any adverse flavor effects compared to a temperature controlled chest freezer used in the rest of the year? Is the wrap a reliable way to heat the wort in the fermenter or does it heat up at the outer wall of the fermenter to a temperature that adversely affects the lager yeast immediately adjacent to the heat source?
I am thinking about off flavors that might come from slightly excessive heat applied at the fermenter wall - not experienced in the situation where ambient cooling is used (my typical approach).
FWIW, I am fermenting and lagering in my garage this winter and don't have a great way to heat up the interior of the chest freezer to keep it warm enough to remain reliably in the fermentation temperature range of the lager yeast. (Garage temp is around or just below freezing this time of the year).